All Questions
28,830
questions
1
vote
4
answers
823
views
True or False: Vaccines are designed to protect against invaders that are encountered rarely, not all the time
I read the following statement in this article:
Vaccines are designed to protect against invaders that are encountered
rarely - not all the time
Is it true? If yes, why?
- 125
6
votes
3
answers
95k
views
Is it possible for a child to grow taller than their tallest parent?
I have heard that offspring can't grow taller than either of their parents but I've also heard that sometimes some gene activation can skip generations. Is it possible for a child to grow taller than ...
- 273
0
votes
1
answer
193
views
How do colds and flu not infinitely recur?
I'm in my third week of university, and a large number of people I know, including myself, still have "fresher's flu", which is probably just a cold and a cough. My lectures are constantly punctuated ...
- 213
3
votes
2
answers
420
views
What would happen if there were no SOX9 in an XY human?
Would testes be produced? If SRY is functional, can it produce other proteins that can direct the production of testes, which may or may not be sterile?
- 51
1
vote
1
answer
348
views
Is the innate immune system capable of identifying all foreign antigens?
I've been studying immunology on my own lately and I would like to know if the macrophages and the other components of the innate immune system are capable of identifying all foreign antigens.
As far ...
- 125
2
votes
1
answer
2k
views
What is the result of meiosis?
Is the result of meiosis ONLY the sex gametes (male and female) which later meet to form a somatic cell?
Sometimes I feel as if my book is hinting towards meiosis is the process where sperm cells meet ...
- 1,381
7
votes
1
answer
649
views
Effects of selection on effective population size
Background
The effective population size ($N_e$) is a central concept of evolutionary biology and is influenced by several parameters. For example: sex ratio bias affects $N_e$ $\left(N_e = \frac{...
- 68.1k
1
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0
answers
83
views
Recovering Coma patient with theoretical full knowledge of heart function
In coma, there is the medullary depression (stage of agony).
Spontaneous respiration and circulation cease i.e. vasomotor center.
There is no full circulatory and respiratory support.
Assume you ...
- 5,149
2
votes
0
answers
435
views
When the mind is highly active, roughly how many neurons become excited in one second?
I'm curios to know how many times neurons send signals in one second when the brain is highly active (Highly active meaning during difficult problem solving, or any task that might bring the brain to ...
- 1,881
4
votes
3
answers
418
views
What is the scientific and common name of this bug?
Captured this under my stereo microscope. Much more beautiful than appearing on my camera sensor.
Can someone help me identify it and explore more?
Also is it having a compound eye ?
Location: New ...
- 571
0
votes
1
answer
157
views
Cell targets of Glybera
So we know that there is a first gene therapy drug in the market out there called Alipogene tiparvovec to address lipoprotein lipase deficiency (LPLD) at a genetic level. Does this genetic drug ...
- 231
1
vote
2
answers
10k
views
What is meant by a muscle fiber being glycerinated?
I was popped this questions today, "what is a glycerinated muscle fiber, and what is required for its contraction," and had little idea. I'm assuming the question is "what's required for its ...
- 3,705
0
votes
1
answer
1k
views
Do the light and dark reactions happen at the thylakoid?
My professor said that light reactions and dark reactions happen at the thylakoid. He did not choose the answer that "both reactions happen at chloroplast".
Isn't the thylakoid a part of the ...
- 147
4
votes
1
answer
577
views
What are "anchor regions" in the human genome?
I've been reading this paper entitled "A high-resolution map of the three-dimensional chromatin interactome in human cells", about interactome in 3D chromatin.
We next applied the above algorithm ...
- 405
1
vote
1
answer
1k
views
Interpretation of graph from evolutionary biology
I am studying evolutionary biology, and been presented with this graph:
I am having some difficulties understand its meaning. For a start, why is time measured as a fraction of the population size? ...
- 111
2
votes
1
answer
921
views
The biology behind tree pruning and hedge trimming
I read two contradictory arguments which both seem logical to me, related to the tree pruning and hedge trimming:
You should prune/cut trees only outside the growing season, when the tree is "...
- 597
2
votes
0
answers
674
views
Do animals have social status as humans in our society?
As our society and it's functioning is closely related to the ones of animals, one question arises: Do animals in nature have social status as humans? People often display it publicly, by buying nice ...
- 21
4
votes
1
answer
165
views
How many traits can a multivariate breeders equation handle?
The multivariate breeders equation (MBE) by Lande predicts the change in a trait $\Delta \bar z$ (response) as
$\Delta \bar z = G \beta$
where $G$ is a genetic variance-covariance matrix and $\beta$...
- 16.1k
2
votes
0
answers
62
views
What do we know about the cellular structure, processes, environment, and immediate ancestors of the last universal common ancestor (LUCA)? [closed]
I am up for all scientifically sound speculations, and sources are highly welcome. I've looked into this quite a bit myself via scholar.google, the wiki article, and /r/askscience.
I'm really looking ...
26
votes
1
answer
2k
views
What are the side-effects of long-term liquid breathing?
I just saw a recent Physics question that mentioned liquid breathing (which I had never heard of before) and I started to wonder about its long-term effects. Let's imagine a person underwent liquid ...
- 1,405
3
votes
0
answers
157
views
Understanding the meaning of $s$ and $t$ in a population genetics equation
Sewall Wright in this article (1937) at the end of page 313 gives the equation:
$$\Delta q = (s+tq)q(1-q) \space\space\space\space\space\space\space\space\space(1)$$
This equation is an ...
- 68.1k
1
vote
1
answer
27k
views
Why would the stroma have a higher pH during photosynthesis?
Here is a question form my test.
If you could measure the pH of the interior of thylakoids and the
surrounding stroma during active photosynthesis what would be the
relative pH of each?
The ...
- 147
2
votes
1
answer
1k
views
Active & passive transport question
If an element, ion or molecule is found in a cell is it possible to tell which method of transport was used? for example if a hydrogen or sodium ion was found in the cell could you tell if it got ...
- 21
1
vote
1
answer
138
views
Preservation of human tissue
At my med school we have human samples (body parts, organs, etc.)
They are soaked in some sort of solution for long term storage. I'm quite sure that it's not formaldehyde as that would be really ...
- 1,381
5
votes
1
answer
213
views
Formaldehyde turns plantar region of feet red?
I'm a freshman med student and I've noticed that on all the feet (and hands) of deceased people that I've worked with, the bottom of the feet always turns red and also the inside of the palm? Why is ...
- 1,381
4
votes
2
answers
1k
views
Proteins with alpha helices alone and beta sheets alone?
I would like to see some examples of proteins with PDB ID so that I can download and see them in VMD software. I need some proteins with alpha helix only and proteins with beta sheets alone.
- 1,133
1
vote
2
answers
3k
views
Organisms using thermal energy as their sole energy source
After seeing this question I remembered that in secondary school we watched a documentary stating something along the lines of "all organisms derive their energy directly or indirectly from the sun. *...
- 195
1
vote
0
answers
70
views
Visualizing GFP in transgenic rice seeds?
I want to express GFP in rice as a method for differentiating transgenic from non transgenic rice seeds. I want to know if I can visualize them using a hand held UV lamp as the GFP I will be using has ...
- 71
3
votes
2
answers
1k
views
Can radiation equilevant to 1 CT (computer tomography) scan causes significant changes in human body?
I've read that CT scan causes radiation equivalent to few hundreds of ordinary X ray scan. It sound scary at the first look of it but I wonder is it the amount considered significant? Can dosage equal ...
- 31
8
votes
3
answers
959
views
Are there any multicellular forms of life which exist without consuming other forms of life in some manner?
The title is the question. If additional specificity is needed I will add clarification here.
Are there any multicellular forms of life which exist without requiring the consumption (destruction) of ...
- 97
6
votes
2
answers
17k
views
Does NADH inhibit gluconeogenesis?
I was told in a physiology lecture that alcohol inhibits gluconeogenesis because 'NADH produced from ethanol catabolism leads to product inhibition'.
But is NADH not a reactant coenzyme of ...
- 175
4
votes
1
answer
147
views
Can chitosan affect the absorption of unsaturated fatty acid?
I know chitosan will decrease the absorption of fat. However unsaturated fatty acid, such as DHA, is beneficial. Does chitosan effect the absorption of unsaturated fatty acid?
- 141
3
votes
1
answer
294
views
What is the advantage to neurons being asymmetrical?
Does having a central axon and dendrites result in any advantage compared to if the neuron was symmetrical?
- 31
12
votes
1
answer
10k
views
Identification of small fuzzy flying insect (pic)
These critters were flying around the neighborhood on an autumn evening in Seattle, WA, USA. Their most notable feature was the small amount fuzz on them. They were quite slow in their flight compared ...
- 223
5
votes
2
answers
850
views
Simulating substitution rate of neutral mutations
I am trying to computationally simulate a population based on the Wright-Fisher model I would like to get to the classic result of the neutral theory of molecular evolution that the rate of neutral ...
- 73
11
votes
4
answers
3k
views
How can I label cryotubes in a way that eliminates the problem of legible hand-writing?
My lab stores biological material (tissue, cells, plasma, serum) in a -130 C, liquid nitrogen freezer. The cryotubes that we use to store a samples are labelled by hand which frequently creates ...
- 1,010
1
vote
2
answers
771
views
Incomplete Dominance and Probability
I have a follow-up question about an in-lecture question (this is not a homework question). As you can see I have already answered the question and the question is closed to further submissions.
In ...
- 499
1
vote
0
answers
66
views
How do we determine a disease's incubation period?
There was a suspected case of Ebola in France, which was later dismissed, since the suspect lastly came into contact with a potentially contaminated person more than 21 days before, which is the ...
- 223
4
votes
1
answer
866
views
Mechanisms of extracellular stimulation of neurons
When stimulating a group of neurons with an electrode, let's say we put it in a region that contains axons, what is the mechanism by which the axons are stimulated?
I've been told electrodes (...
- 143
6
votes
1
answer
6k
views
Neurons with thousands of connections: where are the extra connections coming from?
If every neuron has only one Axon but can can have thousands of (or let's say, even just ten) incoming Axon connections via its dendrites, where are the extra connections coming from?
It seems to me ...
- 1,881
0
votes
1
answer
133
views
Simplest Biological Organism? [duplicate]
What is the simplest biological organism from which a DNA sample has been or could be obtained? Could the resulting DNA be processed and examined in such a way that the resulting information would ...
- 107
0
votes
1
answer
23
views
What studies are there showing the effectiveness of any substance on canine hypertension?
Searching on http://www.ncbi.nlm.nih.gov I could only find the article titled as "Telmisartan Treatment of Refractory Proteinuria in a Dog".
2
votes
2
answers
379
views
What is refractory proteinuria?
I've stumbled upon the article "Telmisartan Treatment of Refractory Proteinuria in a Dog."* What is refractory proteinuria?
*Bugbee AC1, Coleman AE, Wang A, Woolcock AD, Brown SA. J Vet Intern Med. ...
9
votes
1
answer
325
views
Can anyone identify this caterpillar?
Can anyone identify this caterpillar we found on a cauliflower? This was the only photo we could get of it.
Location : Ceres, Fife, Scotland
3
votes
1
answer
7k
views
How does electrolarynx work?
I have heard that this is an effective replacement for patients who have a dysfunctional larynx, partly due to cancer.
I am curious to know the inner working of this device and why such a robotic ...
- 131
2
votes
0
answers
71
views
Why does some skin hold perfume longer than others
I was wondering my girlfriend and I used the same perfume for a while and we sprayed the same place. And after a day her skin still smells nice while mine smells normal.
Will different types of ...
- 205
1
vote
1
answer
263
views
Evolution, What would the first plants have been like?
I am curious what the first plants are thought to have been like, what they may have evolved from, and how much earlier (or later) than animals they are thought to have moved to land, if they even ...
- 505
2
votes
1
answer
247
views
Book-recommendation: Ethology
I am looking for a book that covers the following topics in ethology:
Behaviour
Sensory filtering, reponsive-ness, sign stimuli, learning and memory, instinct, habituation, conditioning, imprinting. ...
- 257
2
votes
1
answer
406
views
Will an 11W UVC lamp kill bacteria?
If I shone a UVC lamp (11W) on something (say for example a plastic phone case) for an hour, would that kill off a noticeable amount of bacteria? That is, if I were to go over the case with a cotton ...
- 181
25
votes
1
answer
2k
views
Additive genetic variance components from LMER in R
I've set up some dummy data in R which makes 40 genetically related lines, they are all siblings within a line so are genetically related by a factor of ½ thus additive genetic variance should be ...
- 16.1k